Pentair FNS Plus 2" Bulkhead with O-ring

The Pentair FNS Plus 2" Bulkhead with O-ring (part number 59023500 or 271096Z / 190143Z depending on the internal vs. external combination configuration) is a specialized, commercial-grade plumbing connection kit designed exclusively for the lower intake and return ports of Pentair FNS Plus Diatomaceous Earth (D.E.) and Quad D.E. pool and spa filtration systems. Injection-molded from thick-walled, high-impact PVC and reinforced engineering polymer composites, this heavy-duty fitting assembly features a large 2-inch internal pipe socket configuration mated to a coarse-threaded bulkhead shaft and a matching premium-grade elastomeric O-ring. Its primary structural role is to establish a secure, leak-proof transition bridge directly through the lower composite wall of the filter tank shell, providing the physical link that connects the internal standpipes or inlet manifolds to the external multiport backwash valve or slide valve piping network.

When threaded down tightly against the tank wall, the accompanying heavy-gauge rubber O-ring compresses to create an absolute watertight and airtight pressure boundary. This enables the filtration vessel to safely handle massive, high-velocity distribution volumes and sustain continuous internal system operating pressures up to 50 PSI without weeping, leaking around the ports, or experiencing structural failure under heavy pump vibration surges. Engineered to survive years of permanent exposure to dynamic hydraulic forces and harsh environments, its robust plastic framework completely resists structural warping, stress cracking, and corrosive degradation from concentrated pool sanitizers like chlorine, bromine, and winterizing acid flushes. Due to its thick-walled, wide-diameter solid plastic architecture and included dense rubber sealing ring, this individual 2-inch bulkhead assembly carries a net product and shipping weight of approximately 0.65 to 0.85 pounds (about 10.4 to 13.6 ounces).